The country code
is the national prefix to be used when dialing TO
that particular country FROM another country. In some
cases you will also need to dial a city or area code. When a
country name appears in the table as a link, there will be additional
information regarding city or area codes.

IDD Prefix (International
Direct Dialing)

The IDD prefix
is the international prefix needed to dial a call FROM
the country listed TO another country. This is followed
by the country code for the country you are calling (see above). The
IDD situation in many countries has been changing regularly.
Some countries have multiple IDDs, with each one used by a different
long-distance carrier.

The NDD prefix is the
access code used to make a call WITHIN that country from
one city to another (when calling another city in the same vicinity,
this may not be necessary). The NDD is followed by the city/area
code for the place you are calling (city/area codes, where applicable,
can be viewed by following the link from the country name on the table
below). Phone numbers are often written in this format:
+44-(0)1224-XXXX-XXXX. This expresses the numbers used for both
international and national long-distance calls. In the example,
+44 indicates the country code, while (0) indicates the NDD.
When dialing from outside the country, the NDD would not be
used after dialing the country code; when dialing from within that
country, the NDD would be used, but the country code would not. NOTE:
All city/area codes used on this site are expressed for use in
international calling; for national calls, prefix the area/city code
with the NDD.

* These
countries are part of the North America Numbering Plan (NANP), though
they may be far removed from North America (and Mexico is not included). The
country code for all NANP countries is 1; the numbers that follow are
used as area codes in the U.S. and Canada and function similarly in
other NANP areas.